package Chaines is
   type Chaine(<>) is private;

   function Concat(S1,S2 : string) return string;
   procedure Concat(S1,S2 : in String; Res : in out String);
   function Chainer(S: String) return Chaine;
   function Dechainer(C: Chaine) return String;
   function Lire_Ligne return String;
   procedure Lire_Ligne(S : in out String);
   function Lire_Ligne_Terminal return String;
   function Tri(S : String) return String;

private
   type Chaine is array(Positive range <>) of Character;
end Chaines;

